1. Field of the Invention
The present invention relates generally to an apparatus and method for performing a scroll function in a portable terminal, and more particularly, to an apparatus and method for performing a convenient and correct scroll function in a portable terminal.
2. Description of the Related Art
Referring to FIG. 1A, a conventional list displayed on a touch screen of a portable terminal is illustrated.
There are various methods for determining a scrolling amount of list items in a conventional portable terminal with a touch screen as shown in FIG. 1A. A first method determines a scrolling amount and speed depending on a drag distance and a speed at which a user carries out a touch and the drag. A second method provides a slide bar 101 in a partial region of a list and determines a scrolling amount according to how a user touches and drags the slide bar 101.
However, in these conventional list item scrolling methods, the user may not correctly input a desired scrolling amount when performing scrolling. In the method for determining a scrolling amount based on a touch-and-drag speed and/or a drag distance, the user may not accurately input the drag speed and distance corresponding to a desired scrolling amount.
Therefore, the user may repeatedly input the incorrect scrolling amount until a focus shifts to a desired position or a desired item appears, which causes frequent occurrence of the repeated touch input.
FIG. 1B illustrates a spin list displayed on a touch screen of a conventional portable terminal. As shown in FIG. 1B, a date can be changed in the spin list by performing a touch and drag. However, when the touch and drag is performed to change a date, the scrolling amount varies according to the drag distance, compelling the user to inconveniently repeat the touch and drag in order to input a correct date.